Strengths

Excellent use of existing patterns:

• The buildBritishEnglishInstructions() function in src/lib/utils/prompt/shared-components.ts:169-190 follows the established factory pattern perfectly
• Consistent integration across all prompt factories (Metis standalone, course-aware, overview; Themis structure)
• Proper use of the buildSection() helper in Themis for consistent XML formatting

Clear, maintainable code:

• The British English instructions are comprehensive yet concise (21 lines)
• Well-structured guidance covering spelling, terminology, and phrasing
• Good use of JSDoc comments explaining the purpose and scope

Documentation excellence:

• Outstanding work record at docs/dev/work-records/2025-10-british-english-emoji-cleanup.md (278 lines)
• Comprehensive impact analysis showing exactly what changed and why
• Roadmap updates reflect completed tasks accurately

Minor Observations

Emoji in validation prompts (line 43):

return `⚠️ PREVIOUS ATTEMPT FAILED VALIDATION ⚠️

The buildRetrySection() function in shared-components.ts:39-53 still uses emoji. Per the work record documentation, this was intentional ("Internal AI communication only"), but consider:

• Consistency: If the goal is emoji-free output, this creates an exception
• AI models don't need visual markers for emphasis
• Alternative: Use [VALIDATION ERROR] or similar text markers

HTML entity inconsistency:
Some components use HTML entities (✓, ×) while others use plain text ("X", "!"). For example:

• ErrorAlert.svelte:39-42 uses plain text: "X", "!", "i"
• ModulePreview.svelte:110,116 uses HTML entities: ✓, ×

Recommendation: Standardize on HTML entities for better rendering across contexts.

No Critical Issues Found

The implementation is solid with no breaking changes or bugs identified.

Minor Considerations

Licence vs License usage:
The British English instructions correctly note the noun/verb distinction:

"licence (noun), license (verb); practice (noun), practise (verb)"

However, consider adding a usage example in the instructions, as this is a common source of errors:

// Current
- licence (noun), license (verb); practice (noun), practise (verb)

// Suggestion
- licence (noun: "software licence"), license (verb: "to license software")
- practice (noun: "best practice"), practise (verb: "to practise coding")

Regression risk - emoji in user-facing error messages:
While the systematic removal from UI components is thorough, verify that no error messages generated at runtime inadvertently include emoji. The ErrorAlert.svelte changes look good, but consider:

• Server-side error messages that might pass through
• Third-party library error messages
• Dynamic content from AI responses (though British English instructions should prevent this)

Positive Impact

Reduced bundle size:

• Removing 54+ emoji instances reduces character count by ~108+ bytes (emoji are typically 2+ bytes)
• HTML entities (✓ = 7 bytes) vs emoji (✓ = 3 bytes), but better compatibility
• Net effect: Negligible but positive

No performance concerns:

• buildBritishEnglishInstructions() is a simple string return (no computation)
• Function is called once per prompt generation (acceptable overhead)
• No additional API calls or async operations introduced

Opportunities

Consider memoization (optional, low priority):
If prompt generation happens frequently in a single session, consider memoizing the British English instructions:

let cachedInstructions: string | null = null;

export function buildBritishEnglishInstructions(): string {
  if (cachedInstructions) return cachedInstructions;
  cachedInstructions = `IMPORTANT: Use British English...`;
  return cachedInstructions;
}

However, this is likely premature optimization given the function is only called once per generation request.

No Security Issues

This PR contains no security vulnerabilities. Changes are limited to:

• Static prompt text generation (no user input processing)
• UI component text replacements (no injection risks)
• Build script console output (no execution risks)

Observations

Prompt injection resistance:
The British English instructions are added to the system prompt, not derived from user input. This is the correct approach and prevents prompt injection attacks.

Output sanitization:
The removal of emoji from user-facing components doesn't change the underlying sanitization strategy. XML output is still validated via moduleValidator.ts (referenced in CLAUDE.md).

Build Verification

The PR description confirms:

• ✅ Build completes successfully
• ✅ TypeScript compilation passes
• ✅ No new diagnostics introduced

Coverage Gaps

Recommended additions (not blocking for merge):

1. Unit tests for buildBritishEnglishInstructions():

   // src/lib/utils/prompt/shared-components.test.ts
   import { describe, it, expect } from 'vitest';
   import { buildBritishEnglishInstructions } from './shared-components';
   
   describe('buildBritishEnglishInstructions', () => {
     it('should return instructions containing British spelling examples', () => {
       const result = buildBritishEnglishInstructions();
       expect(result).toContain('colour');
       expect(result).toContain('realise');
       expect(result).toContain('programme');
     });
     
     it('should mention all content types', () => {
       const result = buildBritishEnglishInstructions();
       expect(result).toContain('Module descriptions');
       expect(result).toContain('Learning objectives');
       expect(result).toContain('Project briefs');
     });
   });

2. Integration test for prompt factories:
   Verify that British English instructions appear in generated prompts:

   it('should include British English instructions in Metis prompt', () => {
     const prompt = buildGenerationPrompt(mockRequest);
     expect(prompt).toContain('Use British English');
     expect(prompt).toContain('colour (not color)');
   });

3. E2E test for actual generation:
   Generate a test module and verify the output contains British spellings:

   it('should generate module with British English spelling', async () => {
     const module = await generateModule(testInput);
     // Check for British spellings in description
     expect(module.description).not.toMatch(/\bcolor\b/);
     expect(module.description).not.toMatch(/\borganized\b/);
   });

Testing Priority

High priority: Unit tests for the new function (ensures the instruction text is correct)
Medium priority: Integration tests for prompt inclusion (ensures factories use it correctly)
Low priority: E2E tests for AI output (expensive, model behavior can vary)

Per CLAUDE.md guidance on "minimal breaking changes" and "zero breaking changes to existing APIs" - the lack of pre-existing tests for prompt components suggests this is consistent with the codebase's current test strategy. However, adding tests would improve maintainability.